From 69f4f9a6f40e2825c93fad4d3adf453c9b33d9bb Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sat, 9 Aug 2008 17:16:40 +0000 Subject: optimize config_read() (by Timo Teras ) function old new delta bb_get_chunk_with_continuation - 176 +176 find_pair 169 187 +18 ... process_stdin 443 433 -10 config_read 549 456 -93 bb_get_chunk_from_file 139 7 -132 ------------------------------------------------------------------------------ (add/remove: 1/0 grow/shrink: 7/7 up/down: 215/-254) Total: -39 bytes --- libbb/parse_config.c | 175 ++++++++++++++++++++------------------------------- 1 file changed, 67 insertions(+), 108 deletions(-) (limited to 'libbb/parse_config.c') diff --git a/libbb/parse_config.c b/libbb/parse_config.c index ace6f3ad3..a0599d4b4 100644 --- a/libbb/parse_config.c +++ b/libbb/parse_config.c @@ -123,137 +123,96 @@ mintokens > 0 make config_read() print error message if less than mintokens #undef config_read int FAST_FUNC config_read(parser_t *parser, char **tokens, unsigned flags, const char *delims) { - char *line, *q; - char comment; - int ii; - int ntokens; - int mintokens; + char *line; + int ntokens, mintokens; + int t, len; - comment = *delims++; ntokens = flags & 0xFF; mintokens = (flags & 0xFF00) >> 8; - again: - memset(tokens, 0, sizeof(tokens[0]) * ntokens); - if (!parser) + if (parser == NULL) return 0; + +again: + memset(tokens, 0, sizeof(tokens[0]) * ntokens); config_free_data(parser); - while (1) { -//TODO: speed up xmalloc_fgetline by internally using fgets, not fgetc - line = xmalloc_fgetline(parser->fp); - if (!line) - return 0; + /* Read one line (handling continuations with backslash) */ + line = bb_get_chunk_with_continuation(parser->fp, &len, &parser->lineno); + if (line == NULL) + return 0; + parser->line = line; - parser->lineno++; - // handle continuations. Tito's code stolen :) - while (1) { - ii = strlen(line); - if (!ii) - goto next_line; - if (line[ii - 1] != '\\') - break; - // multi-line object - line[--ii] = '\0'; -//TODO: add xmalloc_fgetline-like iface but with appending to existing str - q = xmalloc_fgetline(parser->fp); - if (!q) - break; - parser->lineno++; - line = xasprintf("%s%s", line, q); - free(q); - } - // discard comments - if (comment) { - q = strchrnul(line, comment); - *q = '\0'; - ii = q - line; - } - // skip leading and trailing delimiters - if (flags & PARSE_TRIM) { - // skip leading - int n = strspn(line, delims); - if (n) { - ii -= n; - overlapping_strcpy(line, line + n); - } - // cut trailing - if (ii) { - while (strchr(delims, line[--ii])) - continue; - line[++ii] = '\0'; - } - } - // if something still remains -> return it - if (ii) - break; + /* Strip trailing line-feed if any */ + if (len && line[len-1] == '\n') + line[len-1] = '\0'; - next_line: - // skip empty line - free(line); - } - // non-empty line found, parse and return the number of tokens + /* Skip token in the start of line? */ + if (flags & PARSE_TRIM) + line += strspn(line, delims + 1); - // store line - parser->line = line = xrealloc(line, ii + 1); - if (flags & PARSE_KEEP_COPY) { + if (line[0] == '\0' || line[0] == delims[0]) + goto again; + + if (flags & PARSE_KEEP_COPY) parser->data = xstrdup(line); - } - // split line to tokens - ntokens--; // now it's max allowed token no - // N.B. non-empty remainder is also a token, - // so if ntokens <= 1, we just return the whole line - // N.B. if PARSE_GREEDY is set the remainder of the line is stuck to the last token - ii = 0; - while (*line && ii <= ntokens) { - //bb_info_msg("L[%s]", line); - // get next token - // at last token and need greedy token -> - if ((flags & PARSE_GREEDY) && (ii == ntokens)) { - // skip possible delimiters - if (flags & PARSE_COLLAPSE) - line += strspn(line, delims); - // don't cut the line - q = line + strlen(line); + /* Tokenize the line */ + for (t = 0; *line && *line != delims[0] && t < ntokens; t++) { + /* Pin token */ + tokens[t] = line; + + /* Combine remaining arguments? */ + if ((t != (ntokens-1)) || !(flags & PARSE_GREEDY)) { + /* Vanilla token, find next delimiter */ + line += strcspn(line, delims[0] ? delims : delims + 1); } else { - // vanilla token. cut the line at the first delim - q = line + strcspn(line, delims); - if (*q) // watch out: do not step past the line end! - *q++ = '\0'; + /* Combining, find comment char if any */ + line = strchrnul(line, delims[0]); + + /* Trim any extra delimiters from the end */ + if (flags & PARSE_TRIM) { + while (strchr(delims + 1, line[-1]) != NULL) + line--; + } } - // pin token - if (!(flags & (PARSE_COLLAPSE | PARSE_TRIM)) || *line) { - //bb_info_msg("N[%d] T[%s]", ii, line); - tokens[ii++] = line; - // process escapes in token -#if 0 // unused so far - if (flags & PARSE_ESCAPE) { - char *s = line; - while (*s) { - if (*s == '\\') { - s++; - *line++ = bb_process_escape_sequence((const char **)&s); - } else { - *line++ = *s++; - } + + /* Token not terminated? */ + if (line[0] == delims[0]) + *line = '\0'; + else if (line[0] != '\0') + *(line++) = '\0'; + +#if 0 /* unused so far */ + if (flags & PARSE_ESCAPE) { + const char *from; + char *to; + + from = to = tokens[t]; + while (*from) { + if (*from == '\\') { + from++; + *to++ = bb_process_escape_sequence(&from); + } else { + *to++ = *from++; } - *line = '\0'; } -#endif + *to = '\0'; } - line = q; - //bb_info_msg("A[%s]", line); +#endif + + /* Skip possible delimiters */ + if (flags & PARSE_COLLAPSE) + line += strspn(line, delims + 1); } - if (ii < mintokens) { + if (t < mintokens) { bb_error_msg("bad line %u: %d tokens found, %d needed", - parser->lineno, ii, mintokens); + parser->lineno, t, mintokens); if (flags & PARSE_MIN_DIE) xfunc_die(); - ntokens++; goto again; } - return ii; + return t; } -- cgit v1.2.3